ragel(1)

NAME

rlcodegen - code generator for Ragel State Machine Compil

er

SYNOPSIS

rlcodegen [options] file

DESCRIPTION

Note: this is the backend component of Ragel. This program

accepts a machine compiled by the frontend program ragel(1) and

generates either code or a graphviz dot file.

OPTIONS

-h, -H, -?, --help

Display help and exit.

-o file

Write output to file. If -o is not given, a default

file name is chosen by replacing the suffix of the input. For

source files ending in .rh the suffix .h is used. For all other

source files a suffix based on the output language is used (.c,

.cpp, .m, .dot)

-V Generate a Graphviz dotfile instead of code. By de

fault this option writes the dotfile to standard output. The

frontend options -M and -S can be used to specify a subset of the

grammar to write.

-p Print printable characters in Graphviz output.

-T0 Generate a table driven FSM. This is the default

code style. The table driven FSM represents the state machine as

static data. There are tables of states, transitions, indicies

and actions. The current state is stored in a variable. The exe

cution is a loop that looks that given the current state and cur

rent character to process looks up the transition to take using a

binary search, executes any actions and moves to the target

state. In general, the table driven FSM produces a smaller binary

and requires a less expensive host language compile but results

in slower running code. The table driven FSM is suitable for any

FSM.

-T1 Generate a faster table driven FSM by expanding ac

tion lists in the action execute code.

-F0 Generate a flat table driven FSM. Transitions are

represented as an array indexed by the current alphabet charac

ter. This eliminates the need for a binary search to locate tran

sitions and produces faster code, however it is only suitable for

small alphabets.

-F1 Generate a faster flat table driven FSM by expand

ing action lists in the action execute code.

-G0 Generate a goto driven FSM. The goto driven FSM

represents the state machine as a series of goto statements.

While in the machine, the current state is stored by the proces

sor's instruction pointer. The execution is a flat function where

control is passed from state to state using gotos. In general,

the goto FSM produces faster code but results in a larger binary

and a more expensive host language compile.

-G1 Generate a faster goto driven FSM by expanding ac

tion lists in the action execute code.

-G2 Generate a really fast goto driven FSM by embedding

action lists in the state machine control code.

BUGS

Ragel is still under development and has not yet matured.

There are probably many bugs.

CREDITS

Ragel was written by Adrian Thurston <thurston@cs.queen

su.ca>. Objective-C output contributed by Eric Ocean. D output

contributed by Alan West.

SEE ALSO

ragel(1), re2c(1), flex(1)

Homepage: http://www.cs.queensu.ca/home/thurston/ragel/

Ragel 5.14 October 2006

RAGEL(1)